To date, in order to improve forward visibility, it has been proposed that a canopy for covering a perch is supported by two poles in a bulldozer or the like (patent document 1). The patent document 1 discloses that, in order to enhance rigidity of support members for such poles, such support members are shaped like a box having a closed-section structure. According to the patent document 1, such an arrangement not only can enhance forward visibility but also can prevent oscillation of such support members during traveling.
Many wheel loaders use a two-legged canopy similar to the one disclosed in the patent document 1. In addition, adoption of ROPS (roll over protective structure) as a safety standard has been recommended in recent years.
Patent Document 1: JP-UM-A-1-152881